JP2558839B2 - Organic thin film manufacturing method and film forming apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Industrial field of application) The present invention relates to a manufacturing method and a manufacturing method for manufacturing an organic thin film having a uniform structure and having no defects, based on the Langmuir-Blodgett method. The present invention relates to a membrane device.

(Prior Art) In recent years, research and development of electric elements using an organic thin film manufactured by the Langmuir-Blodgett method (hereinafter referred to as the LB method) has been activated. In order to apply an organic thin film manufactured by the LB method to a device, it is important to be able to manufacture a cumulative film having a uniform structure and no defects.

A conventional organic thin film forming apparatus using the LB method is basically a trough that forms a liquid surface for expanding a monolayer, a barrier that compresses the expanded monolayer, and a barrier drive device. And a surface pressure gauge for detecting the surface pressure of the monomolecular film. In the film forming apparatus, for example, only one barrier is provided and an eyeb that drives the barrier in one direction,
There is a type in which two barriers are provided and driven in two directions. When forming an organic thin film based on the LB method using the above device, first dissolve the organic molecule in a developing solvent such as chloroform, and drop this solution drop by drop on the surface of the trough with a syringe. And deploy. Next, the molecules spread on the liquid surface are compressed by driving the barrier. At this time, the surface pressure of the monomolecular film as the surface molecular density of the monomolecular film is monitored by a surface pressure gauge, and the monomolecular film has a predetermined surface pressure π.
Compressed until. Further, the developed monomolecular film is transferred onto the substrate and accumulated by elevating or lowering the substrate, for example, vertically to the liquid surface on which the monomolecular film is developed.

(Problems to be Solved by the Invention) By the way, a surface pressure gauge for detecting a compressed state of a monomolecular film on a liquid surface, a substrate on which the monomolecular film is accumulated, and a barrier for compressing the monomolecular film Since there is a positional shift between the two, the following problems occur. That is, normally
By accumulating the monomolecular film on the substrate, the monomolecular film on the liquid surface decreases and the surface pressure also decreases in the vicinity of the substrate. Then, in the conventional film forming apparatus, it is assumed that the decrease in the surface pressure during the accumulation of the monomolecular film is immediately transmitted to the entire monomolecular film, averaged, and detected by the surface pressure gauge. The operation is to move the barrier in the compression direction until it returns to the surface pressure of. By such operation, it is assumed that the monomolecular film is always accumulated at a predetermined surface pressure.

However, the molecules exhibiting the properties according to the above assumption are very limited such as aliphatic molecules. On the other hand, molecules such as dye-containing molecules and macromolecules have large viscous properties of the monolayer, so the decrease in the surface pressure of the monolayer near the substrate is immediately transmitted to the surface pressure gauge away from the substrate. is not. Here, the viscosity of the monomolecular film developed on the liquid surface is the propagation and relaxation characteristics of stress (surface pressure) generated when a certain area strain is applied to the monomolecular film. That is, the viscosity of the monomolecular film causes a delay in the time required for a change in surface pressure to propagate to the surface pressure gauge. Therefore, when the accumulation operation of the dye-containing molecule or polymer is continued based on the surface pressure detected by the surface pressure gauge, the surface density of the monomolecular film near the substrate continues to decrease. As a result, the density of the monolayer accumulated on the substrate is not constant,
It is impossible to obtain a cumulative film having a uniform structure and no defects.
Further, in order for the monomolecular film on the liquid surface to be transferred onto the substrate, the surface pressure of the monomolecular film must be above a certain value. This value depends on the type of molecule, the hydrophilicity / hydrophobicity of the substrate, and the moving direction of the substrate. Therefore, even if the monolayer can be accumulated under certain conditions, it may even become impossible if the conditions change.

Further, when the barriers, substrate, and surface pressure gauge are spaced, for example, when accumulated, molecules flow radially from the periphery of the substrate toward the substrate. For this reason, even if the monolayers can be accumulated, the molecules become dense and dense along the boundary between the substrate and the monolayer, and a uniform monolayer cannot be obtained.

Therefore, as a means for preventing the non-uniformity of the molecular density distribution in the conventional device, the influence of the viscosity of the monomolecular film is reduced, that is, the surface pressure of the monomolecular film near the substrate is accurately measured by the surface pressure gauge. As can be seen, it is conceivable to slow down the accumulation speed of the monolayer sufficiently. However, this method takes 10 to 1000 times as long as the current time, which is not realistic.

[Structure of the Invention] (Means and Actions for Solving the Problems) The present invention has been made to solve the above problems, and an organic film that has a uniform structure and is free of defects can be obtained in a short time. An object of the present invention is to provide a thin film forming method and a thin film forming apparatus.

In order to achieve the above-mentioned object, the production method of the present invention comprises a step of preparing a liquid surface forming a development region in which a monomolecular film of an organic molecule can be developed; Compressing the developed monomolecular film to a predetermined surface pressure; moving the work having a cumulative surface in a direction perpendicular to the monomolecular film while moving the work along the horizontal direction. And a step of causing the monomolecular film to be accumulated on the accumulation surface by moving it to the front of the accumulation surface.

Further, the film forming apparatus according to the present invention includes a trough that contains a liquid and has a liquid surface that forms a development region in which a monomolecular film of an organic molecule is developed; Means for compressing the surface pressure of the work; a vertical moving means for moving the work along a direction perpendicular to the monolayer; and a horizontal moving means for moving the work along the horizontal direction in front of the accumulation surface. A drive for driving the vertical and horizontal moving means, in which the work moves in the horizontal direction while moving in the vertical direction through the developed monomolecular film, to accumulate the monomolecular film on the accumulation surface. Means and;

According to the present invention, the accumulation operation is performed so that the monomolecular film is not subjected to the area strain due to the decrease in the surface pressure. The basic principle of the present invention will be described below.

According to the present invention, first, the monomolecular film expanded in the expansion region is compressed to a predetermined surface pressure by a compression means such as a barrier. However, according to the present invention, since the monomolecular film can be compressed even by moving the work in a direction parallel to the monomolecular film, it is not always necessary to perform the compression operation of the monomolecular film by the barrier. After the monomolecular film is compressed to a predetermined surface pressure, the work is moved forward at a predetermined horizontal movement speed while lowering the work through the monomolecular film. As a result, the monolayer film of the first layer is accumulated on the accumulation surface of the work. Subsequently, the second monolayer film is accumulated on the accumulation surface by advancing the work at the above-mentioned predetermined horizontal movement speed while raising the work through the monomolecular film. When the vertical movement of the work is switched from ascending to descending or from descending to ascending, the horizontal movement is stopped and the number of substrates is changed without changing the liquid surface area.
mm move. At this time, the monomolecular film is not accumulated on the substrate,
Only the shape of the meniscus formed by the substrate and the liquid surface changes. Then, by repeating the above operation, an n-layer cumulative film is formed on the cumulative surface of the work.

As described above, during the accumulation operation of the monomolecular film, by moving the work in the direction parallel to the monomolecular film, the work moves in the direction of compressing the monomolecular film. Therefore, it is possible to prevent a decrease in the surface pressure of the monomolecular film in the region near the work due to the transfer of the monomolecular film to the accumulation surface of the work. As a result, an area strain of the monomolecular film does not occur, and a film having a uniform structure and accumulating defects can be obtained.

It should be noted that the accumulation operation of the monomolecular film is preferably performed in a state in which the flow of the molecules is regulated so that the monomolecular film does not flow into the region where the work has passed in the development region. In this case, the relative flow of molecules with respect to the cumulative surface of the work during the cumulative operation is a parallel flow toward the cumulative surface. Therefore, it is possible to obtain a cumulative film having a more uniform structure without forming a rough region and a dense region in the molecular flow.
According to the embodiment of the present application, for example, a pair of parallel spacers or a pair of parallel threads defines an elongated expansion region having the same width as the width of the work. The accumulation operation of the monomolecular film is performed in the state of being divided into and. In addition, it is desirable that the width of the expansion region is not fixed and can be freely changed according to the width of the work so that it can correspond to the work of various widths.

The horizontal movement speed of the work is a speed at which the work is moved forward in the development area by an area corresponding to the number of molecules of the film accumulated on the accumulating surface per unit time by the vertical movement of the work. That is, the horizontal movement speed is determined so as to keep the surface molecular density of the monomolecular film in front of the accumulation surface of the work constant, and the determination method includes a forced method and a surface pressure method.

In the forced method, the cumulative ratio of the monomolecular film is set in advance, and the value obtained by multiplying the vertical moving speed by the cumulative ratio is used as the horizontal moving speed. Here, the cumulative ratio is the ratio of the area of the cumulative surface that passes through the monomolecular film when the work moves in the vertical direction and the number of molecules of the film that accumulate on the cumulative surface. For example, when the cumulative ratio is 1, the horizontal movement speed of the work becomes the same as the ascending / descending speed, so the work moves in the direction of 45 degrees diagonally. In addition,
In order to avoid the situation where the monolayer does not adhere to the accumulated surface of the work and the surface pressure of the monolayer rises abnormally, the accumulator is operated while monitoring the surface pressure of the monolayer with a surface pressure gauge. Is desirable.

On the other hand, the surface pressure method detects the pressure acting on the work,
Based on that, the horizontal movement speed of the work is determined. For example, as described above, when an elongated expansion area having the same width as the width of the work is defined and the expansion area is partitioned into the front side and the rear side of the work by the work, the expansion area is expanded in the front area of the work. Assuming that the surface pressure of the monomolecular film is π ₁ and the surface pressure of the monomolecular film developed rearward is π ₂ , the workpiece receives a differential pressure of Δπ = π ₁ −π ₂ from the front side to the rear side. Therefore, if the pressure difference detection unit that detects Δπ is connected to the work and the horizontal movement speed of the work is controlled so that Δπ becomes a predetermined value, the ideal cumulative operation is achieved regardless of the cumulative ratio. It can be performed.

When the surface pressure method is used, the film can be formed in various modes, and the differential pressures to be detected are as follows. For example, when the monomolecular film to be accumulated is expanded and compressed in the area in front of the work and no molecule is expanded in the area behind (π ₂ = 0), Δπ = π ₁ . Further, when the monomolecular film to be accumulated is developed and compressed in the front region and the monomolecular film having low viscosity is expanded and compressed in the rear region so that π ₂ = π ₁ , Δπ = 0. In the latter case, Δπ
If the work can be freely moved back and forth along the molecular expansion region to the position where = 0, there is an advantage that it is not always necessary to know the absolute value of the pressure difference acting on the work.

Furthermore, according to the present invention, since the work can be provided with the function of detecting the surface pressure of the developed monolayer and the function of compressing the monolayer, the monolayer can be compressed in the vicinity of the work. It can be done while controlling the density. Therefore, even if the entire developed monomolecular film is not compressed to a predetermined surface pressure, as long as the surface pressure near the work reaches a desired value, the cumulative operation can be started at that time. Therefore, even molecules having large viscous properties, which may make it difficult to obtain a compressed film having a constant surface pressure, can be accumulated in a short time.

Embodiments Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a film forming apparatus according to a first embodiment of the present invention. The film forming apparatus includes a base 10 on which a trough 12 having a rectangular opening is placed.
The inner surface of the trough 12 is treated with Teflon, and the trough has a water jacket structure.
And the water supply pipe connected to the water jacket
A constant temperature water 16 is made to flow through the trough 14 to control the water 16 in the trough 12 to a predetermined temperature. The liquid surface of the constant temperature water 16 stored in the trough 12 forms a development region 18 in which a monomolecular film described later can be developed. A pair of parallel spacers 20 made of Teflon tape are provided on the trough 12 so as to come into contact with the liquid surface of the water 16, and extend along the longitudinal direction of the trough. Each spacer
Both ends of 20 are fixed to rollers 21, respectively. Also,
The roller 21 is a guide rod fixed to the side wall of the trough 12.
It is attached to 22 so as to be movable along the axial direction of this rod. And these guide rods 22 are spacers 20
It extends in a direction orthogonal to. Therefore, the pair of spacers 20 can move in a direction toward or away from each other. And the deployment area 18 is for these spacers.
It is divided by 20 into an elongated rectangular shape having a width equal to the distance between the spacers. By adjusting the distance between the spacers 20, the width of the expansion region 18 is set to be equal to the width of the substrate 24 as a work described later.

One side of the trough 1 is a front barrier made of an elongated flat plate.
26 is placed and is in contact with the surface of water 16. The barrier 26 extends in a direction orthogonal to the spacer 20 and has both ends at the trough 12
Protruding outward from. Also, on the outside of the trough 12,
A lead screw 27 extending parallel to the spacer 20, that is, extending along the longitudinal direction of the trough is provided, and both ends of the lead screw are rotatably supported by a pair of support plates 28 fixed on the base 10. . A pulse motor 29 for rotating the lead screw 27 is attached to one support plate 28. A guide rail 30 is provided between the pair of support plates 28 and extends parallel to the lead screw 27. A moving table 31 is engaged with the lead screw 27 and the guide rail 30 so as to be movable in the axial direction thereof. Further, one end of the front barrier 26 is connected to the moving table 31 via the arm 32. Therefore, by driving the pulse motor 29, the front barrier 26 is moved along the longitudinal direction of the trough 12, and the monolayer film expanded in the expansion region 18 defined between the spacers 20 is compressed as described later. To do. The pulse motor 29, the lead screw 27, the guide rail 30, the moving base 31, and the arm 32 constitute the barrier moving mechanism 25.

A surface pressure gauge 34 supported by a support plate 33 is arranged above the development area 18. The surface pressure gauge 34 has a filter paper 34a immersed in the development area 18, and measures the surface pressure of the monomolecular film developed in the development area. Then, the pulse motor 29 is controlled by the barrier drive unit 35 based on the surface pressure measured by the surface pressure gauge 34.

A pair of support pillars 36 are erected on the base 10 to form a trough.
Located on both sides of twelve. A lead screw 37 and a guide rod 38 are provided between the support columns 36, and are located above the deployment area 18 along a direction parallel to the spacer 20. A pulse motor 39 for horizontally moving the lead screw 37 is attached to one of the support columns 36. A moving table 40 is engaged with the lead screw 37 and the guide rod 38, and the driving table is moved along the axial direction of the lead screw by driving the pulse motor 39, that is, along the horizontal direction. It is possible. The lead screw 37, the guide rod 38, the pulse motor 39, and the moving table 40 constitute a horizontal moving mechanism 42 for moving the substrate 24 in the horizontal direction.

A lead screw 41 and a guide rod 49 extend downward from the moving table 40 along a direction perpendicular to the deployment area 18. In addition, the lead screw 41
The pulse motor 43 for moving the hydraulic power for rotating is fixed. Then, the lead screw 41 and the guide rod
The movable table 44 is engaged with 49, and the movable table 44 can be moved in the vertical direction by driving the pulse motor 43. Further, the movable base 44 supports a rectangular substrate 24 as a work through a support arm 45. The lead screw 41, the guide rod 49, the pulse motor 43, and the moving base 44 constitute a vertical moving mechanism 46 that moves the substrate 24 up and down along a direction perpendicular to the development area 18.

Further, a slender flat plate-shaped rear barrier 48 made of Teflon is supported on the moving base 44 via a support arm 47, and extends in a direction orthogonal to the spacer 20. The rear barrier 48 is in contact with the liquid surface of the constant temperature water 16 stored in the trough 12 and the back surface of the substrate 24. The rear barrier 48 is movable along the axial direction of the spacer 20 integrally with the moving base 44.

The operations of the pulse motor 39 for horizontal movement and the pulse motor 43 for vertical movement are controlled by the horizontal / vertical movement drive unit 50. Further, the drive unit 50 stores the contact position between the substrate 24 and the development area 18, and has a function of stopping the driving of the pulse motor 43 when the substrate comes out of the development area as the substrate 34 moves vertically. . And horizontal and vertical movement mechanism 4
2, 46, and the drive 50 cause the substrate 24 to move to the deployment area 18
On the other hand, it is moved in the horizontal direction while moving in the vertical direction (ascending / descending). At the same time, the rear barrier 48
It is moved in the horizontal direction while being in contact with the back surface of the substrate 24. This rear barrier 48 prevents the monolayer from leaking to the liquid level behind the substrate, especially when the substrate 24 is separated from the deployment area 18.

Using this film forming apparatus, an LB film is formed as follows.

First, with the substrate 24 not immersed in the water 16 in the trough 12, the spacing between the spacers 20 is adjusted to define the development region 18 having the same width as the substrate 24. In this state, the organic molecule is spread in the region partitioned by the pair of spacers 20 and the front and rear barriers 26, 48. Next, the front barrier 26 is advanced toward the rear barrier 48 to compress the monolayer of organic molecules. At this time, when the output of the surface pressure gauge 34 is equal to or lower than the predetermined surface pressure π, the barrier drive unit 35 advances the front barrier 26 in the compression direction at a constant speed, and the output of the surface pressure gauge matches the predetermined surface pressure π. When it does, it controls to stop the advance of the front barrier. After that, the front barrier 26 is moved forward and backward so that the output of the surface pressure gauge 34 becomes a predetermined surface pressure π. Next, the substrate 24 is immersed in the development area 18. At this time, as can be seen from FIG. 2, the substrate 24 is immersed so that its front surface, that is, the cumulative surface 24a is perpendicular to the longitudinal direction of the spacer 20. Therefore, both side edges of the substrate 24 are substantially in contact with the spacer 20. Also, in this embodiment, the substrate 24 is
24a is positioned so as to be perpendicular to the development area 18.

In this state, by driving the horizontal / vertical movement mechanisms 42 and 46 by the horizontal / vertical movement driving unit 50, the substrate 24 is lowered toward the front barrier 26 while passing through the monomolecular film developed in the development region 18. That is, it advances toward the front of the accumulation surface 24a. At this time, the descending speed and the horizontal moving speed of the substrate 24 are predetermined based on the cumulative ratio of the monomolecular film and are input to the horizontal / vertical moving driving unit 50. In this embodiment, the horizontal / vertical movement drive unit 50 performs compulsory control so that the descending speed of the substrate 24 and the moving speed in the horizontal direction match. Therefore, as shown in FIG.
The substrate 24 moves obliquely downward in parallel through the development region 18, and as a result, the first monolayer film is attached to the accumulation surface 24a.
After the substrate 24 is immersed in the water 16 to a predetermined depth,
The driving of the horizontal and vertical movement mechanisms 42 and 46 is stopped. Then, the horizontal / vertical movement drive unit 50 drives the horizontal and vertical movement mechanisms 42 and 46 again to raise the substrate 24 and advance it to the front of the cumulative film 24a. Therefore, as shown in FIG. 4, the substrate 24 obliquely moves upward in parallel through the development region 18, and as a result, the second monolayer film is accumulated on the accumulation surface 24a. Then, by repeating the above accumulation operation, a desired number of monomolecular films are accumulated on the substrate 24.

Here, as described above, since the development area 18 is partitioned by the spacer 20 to have substantially the same width as the substrate 24, the flow of molecules that wrap around behind the substrate 24 during the cumulative operation, that is, the development area 18 The flow of molecules into the region where the substrate 24 passes is restricted by the spacer 20. Therefore, during the accumulation operation, the flow of the expanded molecules becomes a parallel flow in a direction perpendicular to the accumulation surface 24a of the substrate 24, as shown by the arrow in FIG. As a result, it is possible to prevent a dense region from being generated in the molecular flow. Thus, the spacer 20 constitutes the inflow prevention means 52 that regulates the flow of molecules during the cumulative operation. Further, during the accumulation operation, the substrate 24 is advanced in the direction of compressing the developed monomolecular film. Therefore, the board 24
It is possible to compensate for the decrease in the surface pressure of the monomolecular film in the region near the substrate due to the adhesion of the monomolecular film to the accumulating surface 24a, and it is possible to perform the accumulating operation in the state where the monomolecular film does not have area strain. Become.

Incidentally, during the above accumulation operation, if the monomolecular film does not adhere to the accumulation surface 24a of the substrate 24 for some reason, the developed monomolecular film is excessively compressed by the horizontal movement of the substrate, and as a result, There is a risk of destruction. Therefore, in order to prevent the destruction of such molecules, cumulative operation is performed while monitoring the surface pressure of the monomolecular film by the surface pressure gauge 34, and the cumulative operation is stopped when the surface pressure of the monomolecular film rises abnormally. It is desirable to do so.

Actually, a hydrophobic Si substrate was used as a work, and the polymer film on the liquid surface was accumulated as follows. First,
Molecules of the polypeptide or polyimide were expanded in the expansion region 18 partitioned by the spacer 20, the front and rear barriers 26, 48, and the front barrier 26 compressed the molecules to a surface pressure of 25 dyn / cm. Then horizontal and vertical movement mechanism 4
By driving Nos. 2 and 46 and repeating the above-mentioned accumulation operation, 20 monolayer films were accumulated on the accumulation surface of the Si substrate. When the obtained cumulative film was observed with an optical microscope and a scanning electron microscope (SEM), it was confirmed that the film was uniform and had no defects. Also, when the aqueous solution in the trough 12 was 5 × 10 ⁻⁶ mol of AlCl ₃ solution and the developing molecule was stearic acid, a good cumulative film was obtained.

On the other hand, when using the conventional film forming apparatus, an attempt was made to accumulate monolayers by ascending and descending the substrate and compressing the monolayer by the barrier, but it was not possible to accumulate even more monolayers on the substrate. .

Although the pair of spacers 20 are used as the inflow preventing means 52 in the first embodiment, the inflow preventing means may be configured as shown in FIG.

According to this embodiment, the support shaft 54 is attached to the side wall of the trough 12 located on the back surface side of the substrate 24 and extends along the width direction of the trough. The support shaft 54 is rotatably mounted with a roller 60 around which a regulating tape 56 made of Teflon constituting the inflow prevention means 52 is wound. The regulation tape 56 is formed in the same width as the substrate 24. Further, instead of the rear barrier, a support rod 57 having the same flow as the width of the substrate 24 is provided in contact with the back surface of the substrate. The support rod 57 is supported by the moving table 40 via a support arm 47. The free end of the regulation tape 56 is fixed to the support rod 57, and the regulation tape is in contact with the liquid surface of the constant temperature water 16. Therefore, when the support rod 57 integrally advances with the substrate 24 as the movable table 40 moves, the regulation tape 56
Are drawn from the roller 60 and follow the substrate 24. for that reason,
During the accumulation operation of the monomolecular film, the regulation tape 56 advances while filling the region of the development region 18 through which the substrate 24 has passed, and prevents the inflow of molecules to this region.

Also in the second embodiment configured as described above, the flow of molecules during the accumulation operation can be a parallel flow perpendicular to the accumulation surface 24a of the substrate 24, and as a result, a good accumulation film can be obtained. Can be formed.

5 to 7 show a film forming apparatus according to the third embodiment of the present invention. In this embodiment, the same parts as those in the first embodiment described above are designated by the same reference numerals, and the description thereof will be omitted. Only the parts different from the first embodiment will be described in detail.

In the third embodiment, the pair of spacers 20 are made of Teflon thread instead of the Teflon tape. Further, the rear barrier is omitted and only the front barrier 26 is provided. A Langmuir type surface pressure gauge 34 is attached to the front barrier 26. This surface pressure gauge 34
It has a slender float 61 floating above the liquid surface of the constant temperature water 16, and the float is provided inside the front barrier 26 in parallel.
Both ends of the float 61 are connected to the front barrier 26 via a thin metal foil 62 made of Au or Pt which acts as a leaf spring, and the float is connected to a strain gauge 63 mounted on the front barrier. The monomolecular film is not spread on the liquid surface closed by the front barrier 26, the float 61, and the metal foil 62. Therefore, the float 61 includes a pair of spacers 2
0, the workpiece 64 described later, and the monolayer film expanded in the expansion region 18 partitioned by the float are pressed toward the front barrier 26 by the surface pressure π, and the surface pressure and the elastic force of the metal foil 62 are caught. Stop at the correct position. The position of the float 61 is detected by the strain gauge 63 and converted into an electric signal. From this electric signal, that is, the position of the float 61, the surface pressure π of the monomolecular film is measured. The surface pressure π detected by the strain gauge 63 is input to the barrier drive unit 35, and the barrier drive unit drives the pulse motor 29 of the barrier moving mechanism 25 based on this surface pressure.

The vertical movement mechanism 46 includes a right angle displacement type strain gauge 65 attached to the movement base 44, and the work 64 is supported by the gauge 64 via the support arm 45. When pressure is applied to the gauge 65 via the support arm 45, strain is generated in the gauge 65, and this strain is converted into an electric signal by the dynamic strain amplifier 66. Then, the pulse motor 29 of the horizontal movement mechanism 42
Is driven by the horizontal movement drive unit 50a based on the electric signal. The pulse motor 43 of the vertical movement mechanism 46 is
It is driven by the vertical movement drive unit 50b.

As shown in FIG. 8, in the third embodiment, the work
64 is a holder 67 attached to the lower end of the support arm 45,
And a substrate 24 held by this holder. The holder 67 is formed of a thin rectangular parallelepiped, and its front surface 67a
So as to be perpendicular to the expansion area 18 and perpendicular to the longitudinal direction of the spacer 20.
It is fixed to. The front surface 67a is surface-treated so that a monomolecular film can be attached thereto. Guide grooves 68 extending in the vertical direction are formed on both side surfaces of the holder 67 extending vertically. Further, a pair of wires 69 extending in the vertical direction are inserted through the holder 67 so as to be movable in the axial direction. A hook 70 having a Teflon finish is fixed to each wire 69, and this hook projects to the outside of the holder 67 through a corresponding guide groove 68. Therefore, each hook 70 can move up and down along the guide groove 68. The substrate 24 is a pair of holding members.
The back surface of 71 is held in close contact with the front surface 67a of the holder 67 by 71.

As shown in FIG. 8, when the work 64 is lowered by the vertical movement mechanism 46 in a state where the distance between the spacers 20 is adjusted to be substantially the same as the width of the holder 67, the pair of hooks 70 are moved upward to the corresponding spacers 20. Be hooked from. When the work 64 moves horizontally, the hook 70 slides on the spacer 20 with almost no friction. In addition, the expansion area 18 defined between the spacers 20
Is partitioned by the work 64 into the front side and the rear side of the work. The spacing between the spacers 20 is adjusted to be slightly (about 0.5 mm) wider than the width of the holder 67.

Next, a method of forming an LB film using the film forming apparatus configured as described above will be described.

First, with the distance between the spacers 20 adjusted to be substantially the same as the width of the holder 67, the lower end of the work 64 is immersed in the development area 18, thereby dividing the development area into the front area and the rear area of the work. . In this state, the organic molecules are spread in the front region, that is, the region defined by the spacer 20, the work 64, the float 61 (and the front barrier 26). Next, the front barrier 26
The monomolecular film is compressed to a predetermined surface pressure π ₁ by. Since the rear area is a pure water surface, the surface pressure is π ₂ = 0. At this time, the differential pressure Δπ acting on the workpiece 64
= Π ₁ gives a strain to the strain gauge 50, which is converted into an electric signal by the dynamic strain amplifier 66. Then, the horizontal movement drive unit 50a drives the horizontal movement mechanism 42 so as to move the work 64 forward when the electric signal becomes smaller than a predetermined value and to move the work 64 backward when the electric signal is smaller.

When the work 64 is lowered in a certain minute range, the monomolecular film on the development area 18 is accumulated on the accumulation surface 24a of the substrate 24. At this time, since the molecules in front of the substrate 24 have a large viscosity, the minute decrease in the surface pressure of the monomolecular film near the substrate is not transmitted to the surface pressure gauge 34 attached to the front barrier 26. However, this decrease in surface pressure is detected by the right-angle displacement type strain gauge 34 due to the change in the differential pressure acting on the work 64. Then, control is performed such that the whirl 64 is advanced to compress the monomolecular film until Δπ = π ₁ . Horizontal and vertical movement mechanism while continuously performing such control
The work 64 is vertically moved (raised or lowered) by 42 and 46, and is moved in the horizontal direction, so that the monomolecular film is accumulated on the substrate 24. By the above operation, it is possible to perform a cumulative operation while maintaining a constant surface pressure molecule density without giving an area strain to the monomolecular film on the development region 18.

In fact, after accommodating a 2.0 mM cadmium chloride aqueous solution in the trough 31 and developing pentacosa-9,11-diionic-1-acid (diacetylene molecule), the front barrier 26
Then, the surface pressure was compressed to 25 dyn / cm, and the diacetylene monomolecular film was irradiated with ultraviolet rays from a mercury lamp to be polymerized, and then 20 monolayers were accumulated by the above-mentioned accumulating operation. The X-ray diffraction pattern of the obtained cumulative film shows high-order diffraction peaks, and the calculation shows that the layer spacing is 34 Å
It was confirmed to be a type cumulative film. Also, when the stearic acid was spread in an aqueous solution of 5 × 10 ⁻⁶ mol of aluminum chloride, the obtained cumulative film was a good Y-type cumulative film with an interval of 50 Å.

On the other hand, using a conventional film-forming device, the vertical accumulation method was performed at a fixed position without horizontally moving the substrate, and when the compression operation by the barrier was linked, a polymerized monomolecular film of diacetylene molecules was formed. No one layer could be accumulated.

In the third embodiment described above, a rectangular substrate having the same width as the holder 67 is used as the substrate 24. However, the monomolecular film can be accumulated on a substrate of any shape as long as it is a substrate that fits in the front surface 67a of the holder 67. For example, when a triangular substrate is used, a part of the holder front surface 67a is exposed. As described above, since the front surface 67a is subjected to a surface treatment to which a monomolecular film can be attached, the cumulative surface 24a of the substrate 24 and the exposed portion of the holder front surface 67a are also exposed to the monomolecular film during the cumulative operation. Is accumulated. If the monomolecular film cannot be attached to the holder front surface 67a, the monomolecular film may be excessively compressed by the exposed portion of the holder front surface during the accumulation operation, and as a result, the molecules may be broken. According to this embodiment, it is possible to accumulate monomolecular films on substrates having various shapes without causing such destruction of molecules.

9 and 10 show a film forming apparatus according to the fourth embodiment of the present invention. In the fourth embodiment, the same parts as those in the above-described third embodiment are designated by the same reference numerals, and the description thereof will be omitted. Only parts different from the third embodiment will be described in detail. .

According to the fourth embodiment, the rear barrier 48 is placed on the opposite side of the front barrier 26 across the work 64 of the trough 12. The barrier moving mechanism 72 for moving the rear barrier 48 along the longitudinal direction of the spacer 20 includes the barrier moving mechanism 25.
Similarly, a pair of support plates 73, a lead screw 74, a moving base 75, an arm 76, and a pulse motor 77 are provided.

A Langmuir type surface pressure gauge 78 is attached to the rear barrier 48. The surface pressure gauge 78 also has the same structure as the surface pressure gauge 34 on the front barrier 26 side, and has the float 79, the metal foil 80, and the strain gauge 81 as its constituent members. The pulse motor 77 of the barrier moving mechanism 72 is driven by the barrier driving unit 82 based on the surface pressure of the monomolecular film measured by the surface pressure gauge 78.

A work 64 is supported on the moving table 44 of the vertical moving mechanism 46 via a support arm 45. The upper end of the support arm 45 is rotatably attached along the longitudinal direction of the spacer 20, and is engaged with an electromagnetic clamp 83 attached to the moving table 44. And the support arm 45 is an electromagnetic clamp.
When 83 is released, it can be freely rotated without friction, and when the electromagnetic clamp is operated, it is fixed in a state perpendicular to the deployment area 18. The work 64 is composed of a holder 67 fixed to the lower end of the support arm and a substrate 24 held by a holder, and in a state where the electromagnetic clamp 83 is operated,
The cumulative surface 24a of the substrate is perpendicular to the development area 18. Further, a pair of optical sensors 84 are attached to the movable table 44, and the support arm 45 extends between these optical sensors. When the support arm 45 rotates and deviates from its vertical position, this deviation is detected by the optical sensor 84. Then, the horizontal movement drive unit 50a drives the horizontal movement mechanism 42 based on the detection signal from the optical sensor 84 so that the support arm 45 returns to the vertical position.

The LB film is formed as follows using the film forming apparatus configured as described above.

First, the lower end of the work is immersed in the liquid surface while the space between the spacers 20 is adjusted to be approximately the same width as the work 64, and the development area 18 is divided into a work front area and a work rear area. Then, the front region, that is, the spacer 20, the substrate
24, in the area limited by the float 61 (and the front barrier 26),
Expand the organic molecules you want to accumulate. Also, the rear area,
That is, molecules having low viscosity, such as stearyl alcohol, are spread in the region defined by the spacer 20, the holder 67, the float 79 (and the rear barrier 48). Next, the electromagnetic clamp 83
Is operated to fix the support arm 45 in the vertical position, and the front and rear surfaces of the monomolecular film developed in the front and rear regions reach the same predetermined surface pressure (π ₁ = π ₂ ). Compress by rear barriers 26, 48. When the electromagnetic clamp 83 is released in this state, the front surface and the rear surface of the work 64 have the same surface pressure, so that the work 64 is stationary.

When the work 64 is lowered in a certain minute range, the monomolecular film on the front region is accumulated on the accumulation surface 24a of the substrate 24. At this time, since the molecules in the front region have large viscosity,
A slight decrease in the surface pressure near the substrate 24 is not immediately transmitted to the surface pressure gauge 34 attached to the front barrier 26. On the contrary, in the case of the stearyl alcohol monomolecular film in the rear area, the decrease in the surface pressure near the holder 67 is instantaneously transmitted to the surface pressure gauge 78, which causes the rear barrier 48 to perform the compression operation and expand in the rear area. The surface pressure of the monomolecular film is maintained at a predetermined value. As a result, the surface pressure in front of the work 64 becomes lower than the surface pressure in the rear, the work is extruded slightly forward, and stops when the surface pressures before and after the work are balanced. In this state, the support arm 45 is tilted forward together with the work 64,
This inclination is detected by the optical sensor 84. Then, the horizontal movement drive unit 50a drives the pulse motor 39 of the horizontal movement mechanism 42 based on the signal from the optical sensor 84, and moves the moving table 40 forward until the support arm 45 is no longer tilted. By driving the vertical movement mechanism 46 by the vertical movement drive unit 50b while continuously performing such control, the work 64 is moved in the vertical direction (ascending or descending) and is moved in the horizontal direction, so that the monomolecular film is formed. Is accumulated. By the above operation, the cumulative operation of the monomolecular film is performed on the cumulative surface 24a of the substrate 24 while maintaining a constant surface pressure molecular density without giving an area strain to the monomolecular film expanded on the expansion region 18. be able to.

Also in this embodiment, an organic thin film having a uniform structure and no defects can be formed.

By the above operation, the stearyl alcohol monomolecular film is accumulated on the back surface of the holder 67. However, the monolayer film of the first layer accumulated on the back surface of the holder 67 by the raising or lowering operation of the work 64 is reversibly separated on the liquid surface by the next lowering or raising operation. During this time, the rear barrier
The surface pressure of the stearyl alcohol monolayer is kept at a predetermined value by 48. Therefore, no matter how many layers of the monomolecular film developed in the front region are accumulated on the accumulating surface 24a of the substrate 24, the stearyl alcohol monomolecular film does not decrease and it is not necessary to supplement the molecule.

Actually, 20 layers of diacetylene monomolecular film were accumulated on the substrate in exactly the same manner as in the fourth example. X of the obtained cumulative film
The line diffraction pattern showed higher-order diffraction peaks, and it was confirmed by calculation that it was a good Y-type cumulative film having a layer spacing of 34Å. Similarly, a good cumulative film was obtained when aluminum stearate was used.

Next, a method of shortening the film forming time using the film forming apparatus of the fourth embodiment described above will be described. Although the film forming apparatus of the third embodiment will be described here, as will be described later, since the compression operation by the front barrier is not performed in this method, the front barrier and the Langmuir type surface attached to the front barrier are not necessarily used. No pressure gauge is needed.

First, in the same manner as in the above embodiment, in the area in front of the work 64,
The organic molecules to be accumulated are developed in the region behind the work with a small viscosity, for example, stearyl alcohol. Next, with the electromagnetic clamp 83 being released and the support arm 45 being movable, the stearyl alcohol monomolecular film in the rear region is compressed by the rear barrier 48 until the predetermined surface pressure π ₂ . On the other hand, the front barrier 26 is fixed and the monolayer in the front region is not compressed. As a result, the surface pressure behind the work 64 gradually increases. Here, since the surface pressure in front of the work 64 is close to 0, the work 64 is pushed forward and compresses molecules having high viscosity. That is, as shown in FIG. 11, the rear barrier 48 compresses the stearyl alcohol monomolecular film A, the stearyl alcohol monomolecular film A presses the work 64, and the work 64 is the front high monomolecular film. Compress B. When the surface pressures of these monomolecular films A and B at this time are schematically shown, as shown in FIG. 12, in the region in front of the work 64, only the surface pressure of the monomolecular film B near the substrate 24 is reduced. The surface pressure of the stearyl alcohol monomolecular film A rises and is balanced, but the surface pressure of the monomolecular film B in the region far from the substrate has not yet risen. Substrate like this
In the region near 24, the surface pressure of the monomolecular film has reached a predetermined value, so that the accumulating operation can be performed in the same manner as in the fourth embodiment. Then, while the accumulating operation is being performed, the pressure is also transmitted to the monomolecular film developed in the region far from the substrate 24 and reaches a predetermined surface pressure, so that the accumulating operation can be continuously performed.

Actually, poly (γ-benzyl-L-glutamate) (molecular weight = 100000) was used as a highly viscous molecule, and
20 layers of monomolecular films were accumulated on the substrate by the method shown in Example 1 and the method of shortening the film formation time described above, and the time required for this accumulation was compared.

In the case of the former method, the compression rate of the monolayer by the front barrier 26 should be 0.1 cm / min (1/100 compared to stearyl alcohol, which has low viscosity). Therefore, the width
In order to form a monolayer with a length of 50 cm and a surface pressure of 25 dyn / cm in a trough of 2.5 cm, the molecule was expanded and compressed in a development area having an area twice the area of the desired monolayer. , It took 21 hours. Next, the vertical movement speed of the workpiece is 2 mm /
In addition, it took about 5 hours to accumulate 20 monolayers on the accumulation surface of a substrate having a length of 2.5 cm. Therefore, the total time required was about 26 hours.

On the other hand, according to the latter method, when the accumulation operation is performed while compressing the monolayer by the work itself, the time required to accumulate 20 layers of the monolayer is 7 hours. The operation could be completed in about 1/4 of the time.

 Next explained is the fifth embodiment of the invention.

This example is different from the example described above in that, in addition to the vertical and horizontal movements of the work described above during the accumulation operation of the monolayer, an operation of tilting the work by a predetermined angle with respect to the developed monolayer is added. It's different.

As shown in FIG. 13, when the substrate 24 is lowered through the developed monomolecular film, a meniscus is formed in the boundary region between the substrate surface and the liquid surface, and the liquid surface is bent downward.
Similarly, when the substrate 24 is raised through the monomolecular film, the liquid surface is bent upward as shown in FIG. 14 at the boundary region between the substrate surface and the liquid surface. Such bending of the liquid surface may give an area strain to the monomolecular film developed on the liquid surface. The angle θ formed by the surface of the substrate 24 and the liquid surface is called the contact angle. As is clear from FIGS. 13 and 14, the contact angle (θ ₁ , θ ₂ ) is different. Therefore, when the substrate is switched between the descending operation and the ascending operation, only the shape of the meniscus changes, and there is a time when the monomolecular film does not adhere to the substrate. Then, when the substrate held vertically to the monomolecular film is moved in the horizontal direction at the time when the monomolecular film is not attached, the monomolecular film may be excessively compressed.

Therefore, in the present embodiment, the contact angle θ maintains a constant value even if the angle α of the substrate with respect to the liquid surface changes, and the substrate is inclined by the angle α = 180 ° −θ with respect to the liquid surface. In this state, the cumulative operation is performed. That is,
As shown in Figures 15A and 15B, the substrate
By tilting 24 at an angle α = 180 ° −θ ₁ to eliminate the bending of the liquid surface near the substrate, the substrate is lowered and advanced while keeping the liquid surface flat to accumulate the monomolecular film. Also,
As shown in Figures 16A and 16B, the substrate 24
The substrate is raised and moved forward in the state of tilting the angle α = 180 ° −θ ₂ to accumulate the monomolecular film. In addition,
Since the contact angle is different when the substrate is raised and when it is lowered, these contact angles are measured in advance by an experiment, and the inclination angle α of the substrate with respect to the liquid surface is determined according to the experimental value.

According to the film forming apparatus of this embodiment, in addition to the vertical and horizontal moving mechanisms, a turning mechanism for tilting the substrate with respect to the liquid surface is provided. The film forming apparatus according to the fifth embodiment will be described below with reference to FIGS. 17 to 19. The same parts as those in the above-described embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

A front barrier 26 is provided on the right end of the trough 12,
A barrier moving mechanism 25 for moving the front barrier is provided on the side of the trough. The barrier moving mechanism 25
It has an elongated guide plate 84 extending along the longitudinal direction of the trough 12, and both ends of this guide plate are bent at a right angle. A lead screw 27 is installed between both ends of the guide plate 84, and a pulse motor 29 for rotating the lead screw is attached to one end of the guide plate. A moving base 31 is engaged with the lead screw 27, and one end of the front barrier 26 is fixed to the moving base. Therefore, the compression operation by the front barrier 26 can be performed by driving the pulse motor 29 to move the moving table 31. On the front barrier 26, a Wilhelmy surface pressure gauge 34 for measuring the surface pressure of the monomolecular film on the development region 18 partitioned by the spacer 20 is provided,
The pulse motor 29 of the barrier moving mechanism 25 is driven by the barrier driving unit 35 based on the surface pressure measured by the surface pressure gauge 34. Then, the barrier moving mechanism 25 configured as described above is placed on a surface plate with a vibration isolation mechanism (not shown) via a precision jack 85 for adjusting the height of the barrier moving mechanism and a magnet base 86. There is.

An accumulating mechanism 88 including a horizontal moving mechanism 42, a vertical moving mechanism 46, and a rotating mechanism 87 is provided on the opposite side of the trough 12.

The horizontal movement mechanism 42 has an elongated guide plate 89 extending along the longitudinal direction of the trough 12, and both ends of this guide plate are bent at a right angle. A lead screw 37 is installed between both ends of the guide plate 89, and a pulse motor 39 for rotating the lead screw is attached to one end of the guide plate. Lead screw
The moving table 40 is engaged with 37, and by driving the pulse motor 39, the moving table 40 is moved along the axial direction of the lead screw. The horizontal movement mechanism 42 is placed on the above-described surface plate with a vibration isolation mechanism via the precision jack 85 and the magnet base 86.

The rotating mechanism 87 includes a support column 90 vertically erected on the moving base 40 of the horizontal moving mechanism 42, and a pulse motor 92 fixed to the support column. The pulse motor 92 has its rotary shaft 92
a is provided so as to be orthogonal to the longitudinal direction of the trough 12 and located in a plane parallel to the liquid surface of the trough. The rotary shaft 92a projects from the support column 90 toward the trough 12 side, and an intermediate portion of an elongated rotary plate 93 is fixed to this rotary shaft.
Therefore, by driving the pulse motor 92, the rotating plate 93 is configured to rotate within a plane perpendicular to the liquid surface of the trough 12. A vertical movement mechanism 46 is attached to one end of the rotating plate 93, and a weight 94 for balancing the weight of the vertical movement mechanism is attached to the other end.

The vertical movement mechanism 46 has an elongated guide plate 95 fixed to the rotating plate 93, and this guide plate extends at a right angle to the rotating plate and is positioned in a plane perpendicular to the liquid surface of the trough 12. are doing. Further, both ends of the guide plate 95 are bent at a right angle, a lead screw 41 is installed between these both ends, and a pulse motor 43 for rotating the lead screw is provided at one end. Installed. A moving base 44 is engaged with the lead screw 43,
By driving the pulse motor 43, the moving table 44 is moved along the lead screw 41. The vertical movement mechanism 46 can be rotated by a rotation mechanism 87 in a plane perpendicular to the liquid surface of the trough 12.

A small X-axis stage is mounted on the moving table 44 of the vertical moving mechanism 46.
96 and a support arm 97 are sequentially fixed, and the work 64 is supported by the support arm. The work 64 is composed of a substantially U-shaped holder 67 fixed to the support arm 87 and formed of stainless steel, and the substrate 24 held by the holder. The work 64 is provided so that the accumulating surface 24a of the substrate 24 is located in a plane parallel to the moving direction of the moving table 44 and the rotating shaft 92a of the pulse motor 92 of the rotating mechanism 87. Furthermore, the rotation axis of the pulse motor 92
A red semiconductor laser oscillator 98 is attached to the free end of 92a, and this laser oscillator emits laser light that coincides with the central axis of the rotating shaft 92a.

With the accumulating mechanism 88 configured as above, the trough 12
With respect to the liquid surface of, that is, with respect to the development area 18, the work 64 can be moved in horizontal and vertical directions,
It is possible to adjust the inclination angle of the work with respect to the development area. The horizontal and vertical movement speeds of the work 64 are controlled by the horizontal / vertical movement drive unit 50 connected to the pulse motors 39 and 43 of the horizontal and vertical movement mechanisms 42 and 46, and the inclination angle of the work is determined by the rotation mechanism 87. It is controlled by a rotation drive unit 99 connected to the pulse motor 92. The position of the work 64 is adjusted by the small X-axis stage 96 so that the cumulative surface 24a of the substrate 24 is located on the rotation center of the rotating mechanism 87. This adjustment is performed with reference to the laser beam emitted from the laser oscillator 98. By making such adjustments, the horizontal and vertical movement mechanisms 42 and 46 can be used to
Even when 64 is moved, the substrate can always be rotated with the boundary between the accumulation surface 24a of the substrate 24 and the development region 18 as the central axis.

The trough 12 is a barrier moving mechanism 25 and a cumulative mechanism.
Like the 88, it is mounted on a surface plate with anti-vibration mechanism via a precision jack and magneto base.

Next, a typical accumulation method using the film forming apparatus configured as described above will be described.

In advance, a trough is provided by the precision jack 85 so that the deployment area 18 of the trough 12 and the rotation center axis of the rotating mechanism 87 match.
The height of the barrier moving mechanism 25 and the accumulating mechanism 88 is adjusted.
Further, the position of the work piece 64 is adjusted by the small X-axis stage 96 so that the cumulative surface 24a of the substrate 24 passes through the rotation center axis of the rotating mechanism 87.

Then, first, the pair of spacers 20 define the development area 18 having the same width as the work 64. Next, after rotating the work 64 by the rotating mechanism 87 so that the cumulative surface 24a of the substrate 24 becomes perpendicular to the development region 18, the work is lowered until the lower end of the work comes into contact with the development region 18, and Due to
The expansion area 18 is divided into a front area and a rear area of the work. Subsequently, the monomolecular film is developed in the front region, and the monomolecular film is compressed by the front barrier 26 until a predetermined surface pressure is reached. Next, when the substrate 24 is a hydrophobic substrate, for example, the inclination angle α of the substrate is α = 180 with respect to the contact angle θ ₁ when the substrate descends.
Adjust to ° -θ ₁ (see Figure 15A). Where work 64
Assume upward and forward velocity of + V. in this case,
The moving speed V _H of the horizontal moving mechanism 42 corresponds to the moving speed V _W of the boundary between the accumulating surface 24a and the monomolecular film with respect to the monomolecular film, and the moving speed V _I of the vertical moving mechanism 46 is the above with respect to the accumulating surface 24a. It corresponds to the moving speed V _{S of the} boundary. Therefore, the horizontal movement mechanism 42
And the moving speed of the vertical moving mechanism 46 is the same speed (V _H = | V
_I |), no matter what the inclination angle α of the substrate 24 is, the monomolecular film on the development region 18 is 1 on the cumulative film 24a of the substrate.
It is possible to realize a motion pattern (V _W = | V _S |) that accumulates on a one-to-one basis. Therefore, by advancing the work 64 while descending at the same speed through the monomolecular film, the cumulative surface of the substrate 24 is
The monolayer of the first layer is accumulated on 24a.

Then, the inclination angle α of the substrate 24 is changed to the inclination angle θ when the substrate is raised.
_{According to 2} , adjust to α = 180 ° -θ ₂ (see Fig. 16A). Then, the workpiece 64 is raised and advanced at the same speed through the monomolecular film, so that the accumulated surface 24 of the substrate 24 is
Accumulate a second monolayer on a.

By the above film forming apparatus and accumulating method, the accumulating operation can be performed in a state where a constant surface molecule density is maintained without giving area strain to the monomolecular film expanded in the expansion region.

Actually, pentacosa-9,11-diinonic-1-acid (diacetylene molecule) as a molecule and 2. as an aqueous solution.
Using an aqueous solution of 0 mM cadmium chloride, the developed monolayer was compressed to 25 dyn / cm, and then the diacetylene monolayer was polymerized by irradiating it with ultraviolet rays from a mercury lamp.
The above cumulative operation was performed. The X-ray pattern of the obtained cumulative film showed high-order diffraction peaks, and it was confirmed by calculation that it was a good Y-type cumulative film having a layer spacing of 34Å.
Also, when 5 × 10 ^-6 mol of aluminum chloride aqueous solution is used as the aqueous solution and stearic acid is used as the developing molecule,
A similarly good cumulative film was obtained.

By the fixed position vertical accumulation method using a conventional film forming apparatus, it was not possible to accumulate even one layer of a polymerized monomolecular film of diacetylene molecules on a substrate. Further, even when aluminum stearate was used, a cumulative film could not be formed.

20 to 22 show a film forming apparatus according to another embodiment having a rotating mechanism. In this embodiment, the same parts as those in the above-mentioned fifth embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

According to this embodiment, the guide plate 95 of the vertical movement mechanism 46 is
Is fixed to the moving table 40 of the horizontal moving mechanism 42 and extends vertically upward from the moving table 40. The thin pulse motor 92 of the rotating mechanism 87 is fixed to the moving base 44 of the vertical moving mechanism 46. Here, the pulse motor 92 is provided such that its rotation axis (not shown) extends in a direction parallel to the liquid surface of the trough 12 and at a right angle to the longitudinal direction of the trough. Further, a small X-axis stage 96, a rotary shaft of the pulse motor 92,
The support arm 97 and the work 64 are sequentially attached. As is clear from FIG. 21, the position of the work 64 is adjusted by the small X-axis stage 96 so that the cumulative surface 24a of the substrate 24 is located on the rotation center axis C of the pulse motor 92.

Next, a typical accumulation method using the film forming apparatus configured as described above will be described.

First, the pair of spacers 20 define the development area 18 having the same width as the work 64. Next, after rotating the work 64 by the rotating mechanism 87 so that the cumulative surface 24a of the substrate 24 becomes perpendicular to the development region 18, the work is lowered until the lower end of the work comes into contact with the development region 18, and By the expansion area
18 is divided into a front region and a rear region of the work. Subsequently, the monomolecular film is developed in the front region, and the monomolecular film is compressed by the front barrier 26 until a predetermined surface pressure is reached. Next, when the substrate 24 is, for example, a hydrophobic substrate, the inclination angle α of the substrate is
According to the contact angle θ ₁ when the substrate descends, α = 180 ° −θ ₁
(See Figure 15A). Here, when the horizontal moving speed of the work 64 is V _H , the vertical moving speed of the work is V _V , and the inclination angle of the substrate 24 is α, the moving speed V of the boundary between the accumulation surface 24a and the monomolecular film with respect to the monomolecular film V The moving speed V _{S of the} boundary with respect to _W and the cumulative surface 24a has the following relationship.

V _W = V _H −V _V · cotα, V _S = −V _V / sinα Then, when the inclination angle α is determined, the above speeds V _W and V _S
Calculate V _H and V _V so that becomes a predetermined value. In order to realize the operation mode in which the monomolecular film on the development region 18 accumulates on the accumulating surface 24a of the substrate in a one-to-one manner, it is necessary to establish the relationship of V _W = | V _S |. Therefore, the velocities V _H and V _V have the following relationship.

When the board descends, V _H = (cotα-1 / sinα) · V _V , when the board rises, V _H = (cotα + 1 / sinα) · V _V, and when the board descends at speeds V _H and V _V , work 64 The first monolayer is accumulated on the accumulating surface 24a of the substrate 24 by advancing while lowering.

Then, the inclination angle α of the substrate 24 is changed to the inclination angle θ when the substrate is raised.
_{According to 2} , adjust to α = 180 ° -θ ₂ (see Fig. 16A). Then, through the monomolecular film, by raising and moving the work 64 at the above-mentioned substrate raising speeds V _H and V _V ,
A second monolayer film is accumulated on the accumulation surface 24a of the substrate 24.

Also in the present embodiment configured as described above, similar to the fifth embodiment described above, the cumulative operation is performed while maintaining a constant surface molecule density without giving an area strain to the developed monomolecular film. be able to.

In the fifth and sixth embodiments, when the inclination angle of the substrate 24 is adjusted to α = 180 ° −θ in order to eliminate the bending of the liquid surface due to the meniscus, the contact angle α during the cumulative operation is It is necessary to measure in advance. However, among the molecules, there is a molecule in which the contact angle changes greatly even if the cumulative velocity, the liquid quality of the liquid surface, the temperature, the type of the substrate, the hydrophilicity / hydrophobicity, etc. are slightly changed. When using such a molecule, it is difficult to maintain an ideal cumulative condition.

Therefore, as in the embodiment shown in FIG. 23, instead of the method of measuring the contact angle in advance, in a state in which the work 64 is immersed in the development area 18, the liquid surface detector 100 bends the liquid surface in the vicinity of the substrate 24. Based on the detection signal from the liquid level detector, the substrate 24 is rotated by the rotation mechanism 87 so that the liquid level can be detected.
The inclination angle α of may be adjusted.

The liquid level detector 100 includes a laser generator 102 and a photodiode 104 for position detection, and the photodiode is connected to a pulse motor 92 of a rotation mechanism 87 via a rotation drive unit 99. Laser generator 102 and photodiode 104
Is arranged so that the laser beam is emitted from the laser generator to the liquid surface near the boundary between the accumulation surface 24a of the substrate 24 and the development area 18, and the reflected beam reflected by the liquid surface is incident on the photodiode. . The photodiode 104 is adjusted so that its output becomes zero when the reflected beam is received in a state where the liquid surface is not bent and the liquid surface is kept horizontal. Therefore, when the liquid surface near the substrate 24 is bent upward (when the contact angle θ becomes small), the photodiode
The output of 104 has a positive potential, and conversely, when the liquid surface bends downward (when the contact angle θ increases), the output of the photodiode has a negative potential. Then, the rotation drive unit 99 does not drive the pulse motor 92 of the rotation mechanism 87 when the output of the photodiode 104 is zero, and increases the inclination angle of the substrate 24 when the output of the photodiode is positive. The pulse motor 92 is driven in the direction, and when the output of the photodiode is negative, the pulse motor 92 is driven in the direction in which the inclination angle of the substrate is reduced. By such control, the accumulating operation can be performed while always keeping the liquid surface near the substrate horizontal.

Note that, in FIG. 23, reference numerals 106 and 108 denote a zero-cross detector and a motor driver, respectively.

[Effects of the Invention] As described in detail above, according to the manufacturing method and the film forming apparatus of the present invention, accumulation can be performed without causing strain in the monomolecular film on the liquid surface, and as a result, the viscosity can be increased. Even if a large molecule is used, an organic thin film having a uniform structure and no defects can be produced in a short time.

[Brief description of drawings]

1 to 4 show a manufacturing apparatus according to a first embodiment of the present invention, and FIG. 1 is a perspective view showing the entire apparatus,
FIG. 2 is a plan view schematically showing the above apparatus, FIGS. 3 and 4 are schematic views each showing a process of accumulating a monomolecular film, and FIG. 5 is a second embodiment of the present invention. 6 to 8 are perspective views of a film forming apparatus according to the present invention, FIG. 6 is a side view of the apparatus, and FIG. 7 is a plan view of the apparatus. FIG. 8 is a perspective view of a holder, FIGS. 9 to 12 show a manufacturing apparatus according to a fourth embodiment of the present invention, FIG. 9 is a side view of the apparatus, and FIG. FIG. 11 is a plan view of the apparatus, FIG. 11 is a view schematically showing a compressed state of the developed monolayer, FIG. 12 is a graph showing the compressed state, and FIGS. Shows an example,
13 and 14 are side views showing the contact angle between the substrate and the liquid surface when the substrate is descending and ascending, respectively.
FIGS. 15A and 15B are side views schematically showing the cumulative steps when the substrate is lowered, FIGS. 16A and 16B are side views schematically showing the cumulative steps when the substrate is raised, and FIG. , A perspective view showing a manufacturing apparatus according to a fifth embodiment, FIGS. 18 and 19 are side views and a front view of the accumulating mechanism, and FIGS. 20 to 22 show a sixth embodiment of the present invention. FIG. 20 is a perspective view showing the whole of the above apparatus,
21 and 22 are side and front views of the accumulating mechanism, and FIG. 23 is a diagram schematically showing a modification of the position detecting mechanism and the rotation driving mechanism. 12 …… Trough, 18 …… Development area, 20 …… Spacer, 24…
... Substrate, 24a ... Cumulative surface, 25 ... Barrier moving mechanism, 34 ...
… Surface pressure gauge, 35 …… barrier drive, 42 …… horizontal movement mechanism, 46 …… vertical movement mechanism, 50 …… horizontal / vertical movement drive section, 50a …… horizontal movement drive section, 50b …… vertical movement drive Department,
64 …… Workpiece, 67 …… Holder, 87 …… Rotation mechanism, 88 ……
Accumulation mechanism, 99 ...... Rotation drive unit.

Claims (4)

(57) [Claims] 1. A step of preparing a liquid surface for forming a development region capable of developing a monomolecular film of an organic molecule; a step of developing a monomolecular film of an organic molecule in the molecular development region; The step of compressing the monolayer to a predetermined surface pressure, and moving the work piece having the accumulating surface in the direction perpendicular to the monolayer, while moving it in the horizontal direction in front of the accumulating surface so that it is on the accumulating surface. A method of manufacturing an organic thin film, comprising the step of accumulating monomolecular films. 2. The method for producing an organic thin film according to claim 1, wherein the accumulating step is performed in a state where the accumulating surface of the work is inclined at a predetermined angle with respect to the spread area. 3. A film forming apparatus for accumulating an organic thin film on a cumulative surface of a work, the trough containing a liquid and having a liquid surface forming a development region in which a monomolecular film of organic molecules is developed, A compression means for compressing the developed monomolecular film to a predetermined surface pressure, a vertical moving means for moving the work in a direction perpendicular to the monomolecular film, and a cumulative surface of the work in a horizontal direction. And a horizontal moving means for moving the work vertically along the vertical direction through the unfolded monomolecular film, and driving the vertical and horizontal moving means so that the work moves on the accumulated surface. A film forming apparatus comprising: a driving unit for accumulating a monomolecular film. 4. A rotating means for rotating the work so that the accumulated surface is inclined at a predetermined angle with respect to a development area,
The film forming apparatus according to claim 3, wherein the driving means drives the horizontal and vertical moving means in a state where the accumulating surface is inclined by a predetermined angle.